Bisabolane and chamigrane sesquiterpenes from the soft coral Pseudopterogorgia rigida

A chemical investigation of the organic extract of the tropical soft coral Pseudopterogorgia rigida afforded 27 sesquiterpenes, among which one chamigrane (1) and seven bisabolanes (2-8) are new natural products. The structures of compounds 1-8 were deduced by analysis of their NMR and MS data. The full assignment of the spectroscopic data of four aromatic bisabolanes previously reported as semisynthetic products (11, 19, 22, 23) is reported. (C) 2014 Published by Elsevier B.V. on behalf of Phytochemical Society of Europe.